I have an Aurender Music Server / Streamer. It only outputs USB. Using a Curious Evolved USB Cable I have never had a single issue with any DAC recognizing the USB connection...DAC's used are Schiit Gungnir MB, Chord Qutest, MHDT Labs Pagoda, the DAC in my old Parasound P6....never an issue and the sound is fantastic. If you just hate USB you can buy a USB reclocker / SPIDF converter that you can go USB in and COAXIL or I2S out. You place this between your server/computer and dac.
USB sucks
USB really isn‘t the right connection between DAC and Server: depending on cables used, you get very different sound quality if the server manages to recognise the DAC at all. Some time ago I replaced my highly tuned Mac Mini (by now-defunct Mach2mini, running Puremusic via USB) with an Innuos Zenith Mk3. For starters I couldn‘t get the DAC (Antelope Zodiac Gold) and server to recognise each other, transmission from the server under USB2.0 wasn‘t possible because the server is Linux based (mind, both alledgedly support the USB2.0 standard) and when I finally got them to talk to each other (by using Artisansilvercables (pure silver) the sound quality was ho-hum. While I understand the conceptual attraction to have the master clock near the converter under asynchronous USB, the connection‘s vagaries (need for exact 90 Ohms impedance, proneness to IFR interference, need to properly shield the 5v power line, short cable runs) makes one wonder, why one wouldn‘t do better to update I2S or S/PDIF or at the higher end use AES/EBU. After more than 20 years of digital playback, the wide variety of outcomes from minor changes seems unacceptable.
Since then and after a lot of playing around I have replaced the silver cables by Uptone USPCB rigid connectors, inserted an Intona Isolator 2.0 and Schiit EITR converting USB to S/PDIF. Connection to the DAC is via Acoustic Revive DSIX powered by a Kingrex LPS.
The amount of back and forth to make all this work is mindboggling, depending on choice of USB cables (with and without separate 5V connection, short, thick and God-knows what else) is hard to believe for something called a standard interface and the differences in sound quality make any review of USB products arbitrary verging on meaningless.
Obviously S/PDIF gives you no native PCM or DSD but, hey, most recordings still are redbook, anyway.
Conversely it is plug and play although quality of the cable still matters but finally it got me the sound quality I was looking for. It may not be the future but nor should USB, given all the shortcomings. Why is the industry promoting a standard that clearly isn‘t fit for purpose?
Finally, I invite the Bits-are-bits naysayers to go on a similar journey, it just might prove to be educational.
Since then and after a lot of playing around I have replaced the silver cables by Uptone USPCB rigid connectors, inserted an Intona Isolator 2.0 and Schiit EITR converting USB to S/PDIF. Connection to the DAC is via Acoustic Revive DSIX powered by a Kingrex LPS.
The amount of back and forth to make all this work is mindboggling, depending on choice of USB cables (with and without separate 5V connection, short, thick and God-knows what else) is hard to believe for something called a standard interface and the differences in sound quality make any review of USB products arbitrary verging on meaningless.
Obviously S/PDIF gives you no native PCM or DSD but, hey, most recordings still are redbook, anyway.
Conversely it is plug and play although quality of the cable still matters but finally it got me the sound quality I was looking for. It may not be the future but nor should USB, given all the shortcomings. Why is the industry promoting a standard that clearly isn‘t fit for purpose?
Finally, I invite the Bits-are-bits naysayers to go on a similar journey, it just might prove to be educational.
150 responses Add your response
Why some USB cables are better is due to better edge detection on an analogue square wave. Well of course it’s not perfectly square, just as a sign wave from a power station isn’t a perfect sinusoidal wave. My qualification is that I am an Instrumentation technician, and Automation programmer. Please go and do some actual studies and research before claiming that there is no difference between different conductors and cable materials and geometry/shielding. Get on a decent oscilloscope and go see for yourself. I have worked in a business that controls robots, and they used EtherCat protocols. I have spent hours in a classroom studying theory, in order to get my qualifications. For example Cat 5, 5e, 6, 6a, 7, 8 Ethernet cable standards. This isn’t for fashion, there are actual differences, measurable differences in performance. Try a quality USB (I used to work for a reasonably well known USB cable maker in Australia, an an employee) with a quality USB DAC sometime and hear the difference. Digital is an encoding system, transfer of data is all totally analogue and electrical. Edge detection is to measure over time when a electrical signal is powered and the circuit is powered down, noise is a real issue. There’s nothing in the cables passing little ones and zeros across the cable. EDIT: excuse my rant, I am just trying to ensure people don't get misinformed and miss out on relatively cheap solutions that will significantly increase performance. |
USB does carry and introduce a noticeable amount of noise into the DAC, even with high-quality USB cables. I have found much improved performance by putting an intermediary device in between my music server and DAC. Today, I have my Mac Mini Roon Server's USB output connected into a SingXer SU-6. Then the SingXer SU-6 outputs AES/EBU into my Mytek Manhattan II DAC. This is MUCH improved in noise floor and sound quality, and was very simple to A/B test the Mytek's USB input versus AES. Also, if I take the WCLK output from the SingXer SU-6, I get a more natural sound from less jitter. I have also used a Simaudio Moon MiND 2 streamer in the exact same role, and had similarly positive results compared to straight USB. I upgraded to the SingXer SU-6 so I could support my DSD128 (DoP 1.0) and up to 384K/24bit files via the Myth AES/EBU inputs. I have heard several other devices that can give the exact same benefits compared to straight USB, so there are a lot of options out there... |
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I wrote this post mainly to alert people that they might be missing out on substantially improved sound by improving/working around their USB connection, provided they can get it to work at all. That in my mind disqualifies USB as a future proof industry standard, irrespective of all the design progress having been made |
+1 to steakster and Rix. Since the USB ports of most server devices also provide output power for USB peripherals, they inherently introduce some noise from the music server's power supply into the USB output. That noise is nowhere near enough to effect the 0's and 1's, but if it is carried into the USB input of the DAC, it can effect the sound quality. If 1 millivolt of noise were to be introduce into the DAC's analog output, it would create a noise floor at -70dB. Many higher end USB cables reduce the noise carried from the music server to the DAC's USB port. Also, using a LPS on the server instead of SMPS generates less power supply noise at the server's USB output. Converting USB into a format like AES/EBU or S/PDIF that does not carry power also reduces DAC noise. Even grounding the DAC circuit board (not the same as chassis) will helps to reduce DAC output noise in in some cases. At the end of the day converting 0's to 1's in most modern audiophile DAC's should yield a good analog output signal. However, if even a small amount of analog noise is added to that signal output, there is a noticeable change in the noise floor through an audio system capable of 100dB or greater dynamic range. I know that some people and systems are less sensitive to low levels of analog noise, but I personally prefer my music with as low of a noise floor as possible... |
“in my mind disqualifies USB as a future proof industry standard, irrespective of all the design progress having been made”. @antigrunge2, It doesn’t looks like you’ve learned anything since you started the thread. Unfortunately, yours was a isolated case of bad hand shake between your DAC and streamer. It’s got nothing to do with ‘USB sucks’ as you continue to maintain in your posts. I can even go further to state that it’s not your server, it’s the USB implementation in your DAC which is probably OUTDATED! Instead of blaming USB protocol, did you try to pair Innuos with another DAC? I say this because I went through same ordeal with my ARC DAC9 to make it compatible with Linux based streamers/ servers. The original USB board in DAC9 at its release was only compatible with Windows operating system not Linux. Once I upgraded the USB board, the DAC worked flawlessly with Windows and Linux based servers / streamers. |
@rixthetrick You may be impressed with your own qualifications but if your experience tells you that USB is an analog transportation medium then you were learning at the wrong places. A 5V voltage "analog" signal is digitally encoded and decoded. once encoded it's no longer an analog signal. Period. Yes, it is later decoded to an analog signal (isn't science great?) but that's besides the point. You are misleading this post's readers by suggesting otherwise. |
A lot of misinformation being spun here. I think the title of the thread pretty much sums up the irrationality in so far as a sweeping generalization. If I said McIntosh sucks, I suppose it would be due to my personal experience which is certainly valid as is the OP's umm, OP. Certainly if I was struggling with a certain technology with my gear it would be frustrating, I totally get it. However, the time that USB has been around and matured is very evident and in many cases surpassed most other interfaces. That's not to say it doesn't have issues. I think one has to approach such statements with some maturity and understanding of the technology. There isn't one "connection" type that exists that someone at some point hasn't had an issue with their gear. If the designer and the implicit design intent is focused entirely on USB, or opt, or spdif, or Ethernet etc....chances are THAT interface will acell above any other in that particular product. Its actually very apparent in numerous products and nowadays, USB pretty much dominates most product interfaces. Creating a really GOOD Ethernet interface in a DAC is very expensive. The same goes for pretty much all other types > USB, i2s, opt etc... . Sure you can load up a component with everything under the sun, but it's THE IMPLEMENTATION of said interface that matters. This has been stated ad nauseam throughout most forums. My .02 |
@steakster - I think what @rixthetrick was getting at is that any signal on a cable is inherently analog. While it represents digital data, the signal does not instantaneously transition from one voltage to another to represent 0s and 1s. The interface and cable must maintain good signal integrity to properly confer the digital data. However, USB is a fairly robust interface. It’s designed to transfer digital data reliability in very low cost implementations. It can start to have problems with long cable lengths, but within reasonable limits, it does a great job of reliably transferring data and can easily handle the requirements of high resolution audio. As has been pointed out, it is not optimized for minimum noise transfer between devices. It’s designed to be a reliable, inexpensive interface between digital devices. So care must be taken in the design and implementation of the server/streamer, interface cable, and DAC to minimize the effects of any electrical noise generated by the source or picked up along the way. That doesn’t make it a bad interface. In most regards, all other digital audio interfaces have the exact same issues. It’s true that USB carries a power connection, but this can easily be ignored/dealt with by the DAC. The big advantage of USB (and Ethernet) over older digital audio interfaces (spdif/optical/AES3) is that they are asynchronous and therefore won’t introduce audio sample jitter into the mix. Sure, you can put a lot of engineering effort and cost into the digital source to reduce jitter on these older interfaces (spdif, etc.), but the interfaces themselves make it impossible to achieve as good of results as the same effort/cost applied in the DAC itself where clocks and transmission line impedances are much easier to control. There is certainly value in reducing the noise that is conveyed on the USB interface since this just makes the DACs job easier. Using a USB source device that has a good low-noise power supply and using a good cable can often help. This isn’t (or certainly shouldn’t) have any effect on the actual data that arrives at the DAC, but can reduce the amount of electrical noise that the DAC has to deal with. |
Since Rednet is a proprietary Focusrite interface that limits you to using Dante type pro audio interfaces that no high end DAC uses, doesn't that kind of make it so limited in scope that it really doesn't pertain to a discussion on an audiophile forum? AND it really is intended for a different purpose especially longer runs that USB can't deal with, handling many more channels in a recording studio, , as well as uses where latency is important, not home audio. Also, since there are very few devices that give you a choice of Dante or USB like a Lynx Hilo does, how can you prefer Dante when you can't compare the 2? That said, I'm all in on pro audio interfaces. You can see the heart of my system is an Antelope Eclipse 384, but it uses USB and sounds wonderful. |
Not limited at all, Herman, except for direct DSD. A Rednet 3 in hifi terms is equivalent to a usb/spdif converter (and the reverse), except that the USB is replaced with ethernet. It's currently used with a Khadas Tone Board although I did try it briefly with a Holo DAC. In both cases Rednet made USB sound grainy to my ears. Yes, it's overkill in that only two of 32 channels on the device are being used! I'm sure your Antelope sounds wonderful :) |
Is there really an advantage to not using a combined Streamer / DAC? I have Roon Nucleus + (yes expensive but flawless in operation, don't ever even need to look at it, located by modem in my office) and two DACs, Auralic VEGA 2 and MOLA MOLA Tambaqui, both of course ROON endpoints. The Nucleus + has installed internal hard drive so there also is no separate network attached storage to fool with. This did replace my aging Mac Mini which gave me fits when it needed rebooted or whatever. Both DACs have network bridges and are trouble free. NO USB cables, no compatibility issues, less boxes. Both are hard wired vs wifi. I did need to update my switch and some ethernet cables, but this would benefit anyone. I am into audio, not computers. Ken |
Thanks for the info Furzy, looks interesting, I may try it to compare to USB as the Antelope has spdif and optical inputs. However, even though I doubt it would be significant, those inputs are limited to 192 and 96K respectively whereas I can feed it up to 384k upsampled in Roon from USB. On the other hand, a Raspberry Pi with digital card will do the ethernet to spdif for about $100 wonder if Roon would see the Rednet as an audio device like it does a Pi? |
Interesting, they're all worth a try if you can do so. There is actually a Dante device at least near the same price as the Raspberry Pi, the Audinate AVIO Dante 2x2 AES3/EBU Adapter. I think it only goes to 96K though. I have run Spotify through the Rednet 3, but couldn't listen to the loss in sound quality compared to uncompressed music. |
@rixthetrix Wow, a "technician" that doesn't know about detection level, encoding, checksumming and buffering... You are mixing things and ethernet category of cables have nothing to do with USB cables... Obviously, you don't know about high-speed differential pairs, linear feedback shift register, 8b/10b encoding, etc etc etc. And about transmission of digital signal being "analog", that's just plain talking for nothing... Of course, every electrical signal could be described as" analog" but that's not the point... We're talking digital communication and encoding, bit detection, etc... In a computer, this is the same principle, be it in gigahertz range... "There’s nothing in the cables passing little ones and zeros across the cable." Oh and what is digital transport then? And ethernet? And transmission lines in a computer? Incredible... And the top of the top:" excuse my rant, I am just trying to ensure people don't get misinformed and miss out on relatively cheap solutions that will significantly increase performance." Wow... That's exactly what you do... I can tell you didn't pass any degree, you should study a bit before trying to look that you know something, you just don't... Go get a good engineering book and read before throwing crap like you did... if you're up to understand something... Here is a free MIT book, try to read and understand it... http://www.mit.edu/~6.450/handouts/6.450book.pdf |
@papagiorgo Another non tech that don’t understand and speak out BS... "USB does carry and introduce a noticeable amount of noise into the DAC, even with high-quality USB cables." The, you have a badly designed USB DAC... Throw it to trash, it is where it belongs... @jaytor Your point is exactly what everybody should understand here! @CDD same as papagiordo, throw you trash DAC where it belongs... |
@herman "Transmitting audio data in realtime is not the same as transferring TeraBytes of data files. You should look into it before making such statements." Ok go ahead and explain me how it is different!! YOU should study about async digital communication, encoding and buffering... It’s obvious that you just plain don’t know... |
And for all those who put BS on this board, just grab this before making a fool of you... https://www.amazon.com/Principles-Digital-Communication-Robert-Gallager/dp/0521879078 |
@herman "Transmitting audio data in realtime is not the same as transferring TeraBytes of data files. You should look into it before making such statements." https://darko.audio/2016/05/gordon-rankin-on-why-usb-audio-quality-varies/ I will defer to Gordon Rankin who I trust more than somebody angrily ranting on this forum The three main USB transmission protocols are Bulk, Interrupt and Isochronous. Bulk (used for data transfer to a hard drive) and Interrupt are error-correcting. Isochronous (used for audio) is not.” “Bulk and Interrupt are immediately NAK (negative acknowledgement). The receiver is designed to detect a bad packet immediately and the packet is resent.” “For USB audio, the receiving device is basically translating a serial stream of data with a clock interwoven throughout. At the end of the packet sits some sort of block check. If the block check does not match the data then that packet is flagged as an error.” “With Isoschronous USB transmission, packets are sent without any error correction / resending. But guess what? This is the USB protocol used for audio frames. The bad news is they are not error-free. The good news is these Isochronous frames are afforded the highest priority in the system.” |
@jaytor sed:
I think what @rixthetrick was getting at is that any signal on a cable is inherently analogHow's that? With all due respect, do you actually understand what makes analog signals analog and how digital signals are different. ABout the only similarity is that they can both use wire as a transport media. If a car operates on roads and a elephant walks down the same road, does that make the elephant a car? |
Sorry, back to the difference in sending data over USB like we do with file transfers and audio uses.. to further my point above , despite what the angry poster says, .Audio and file transfers are different as file transfer protocols have error correction from Mojo Audio
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@jaytor sed:I think what @rixthetrick was getting at is that any signal on a cable is inherently analogHow’s that? With all due respect, do you actually understand what makes analog signals analog and how digital signals are different. ABout the only similarity is that they can both use wire as a transport media. If a car operates on roads and a elephant walks down the same road, does that make the elephant a car? It depends on how you look at it. "The only similarity is that they can both use wire" isn’t quite right. Digital is by definition binary.... high/low, 1/0, true/false, whatever. Electrically, those 2 states can be represented by 2 different frequencies, 2 phases, etc. . With USB those 2 digital states are 2 voltage levels. Analog information is represented by constantly changing voltage levels with an infinite number of possibilities. So yes, they are the same in that both analog and digital information are represented by voltage levels. Since the digital voltage level can’t change instantaneously (a perfect square wave) it bears some resemblance to an analog signal’s infinite voltage levels. However, does any of that really matter? With analog, errors are a given. It is impossible to maintain 100% accuracy throughout the analog chain. On the other hand, digital errors are very, very low and in a well designed system, for all practical purposes they are zero. In any case, it is a red herring that distracts from the topic of whether or not USB sucks BTW.... it does not |
herman Digital is by definition binary.... high/low, 1/0, true/false, whatever ...Agreed. Analog information is represented by constantly changing voltage levels with an infinite number of possibilities.That’s a common misnomer. It could only be true if the bandwidth of the analog system were infinite, which is impossible, of course. So just like digital, analog is bandwidth limited. Its resolution is finite. Since the digital voltage level can’t change instantaneously (a perfect square wave) it bears some resemblance to an analog signal’s infinite voltage levels.Not really. That the square wave isn’t perfect doesn’t make it an analog signal. |
Not really. That the square wave isn't perfect doesn't make it an analog signal. yes, we agree, I am only trying to make the point that the digital signal does not strictly meet the definition of 2 and only 2 distinct states since it takes some time to transition. Like I also said, it really makes no difference to the discussion of whether or not USB sucks = a red herring Analog information is represented by constantly changing voltage levels with an infinite number of possibilities.That’s a common misnomer. It could only be true if the bandwidth of the analog system were infinite, which is impossible, of course. So just like digital, analog is bandwidth limited. Its resolution is finite. It is not a misnomer, my statement is absolutely correct. There are an infinite number of voltage levels between any 2 levels. It has nothing to do with bandwidth. |
You're arguing that analog systems have infinite resolution, which is simply false. It's a commonly held belief, though. I'm not arguing, I'm stating a fact, which has nothing to do with bandwidth or resolution. You are confusing bandwidth which you brought up earlier and resolution now and whatever else with the simple fact that an analog waveform will, at any point in time, be at any one of an infinite number of possible levels. Anything continuous like an analog waveform has an infinite number of possible points. Q: how many point are there on a line? A: an infinite number Let's say for example your DAC has a minimum output level of zero volts and a maximum of 2 V and the output is a sine wave varying between those 2 levels. If you are correct, tell me what level between and 0 and 2 is it incapable of producing? What voltage levels does it skip on its way from 0 to 2v? .0000001 ? .000001 ? .00001 ? .0001 ? .001 ? .01 ? .1 ? 1 ? 1.1 ? and so forth none of these and none of the other possible infinite number of possible levels between these |
USB for a DAC??? Never.I guess you realize that dogmatic statements like this without any context and nothing to back them up are basically worthless and add nothing to the conversation? Noise in the signal will mask any resolution below the noise level. what noise in what signal ? Are you claiming noise in the digital signal somehow makes it thru to the analog output or something else? If you are, isolating the incoming noise from the USB line from the rest of the system is pretty well understood. |
I was writing about the infinite resolution statement. While voltage levels from say 0 to 2 volts may have infinitely possible levels (I'm not even sure of this due to the quantum nature of the universe) being able to read those infinitely small changes (resolution) can't be done due to external noise entering the wire. Even background cosmic radiation will limit measurable differences. |
There’s at least one clown on this thread who has no business saying anything about audio. You figure out who. He goes by theory and not his ears, if he's ever really listened at all. My experience... Cables make a huge difference for sure. External clockers make a huge difference. We’re not talking about hooking up a USB printer. Jitter is the plague of digital audio. It can come from transports and servers. There are devices that go in the audio path to clean it up. How do I know all this? I use my ears. |
USB for a DAC??? Never. I guess you realize that dogmatic statements like this without any context and nothing to back them up are basically worthless and add nothing to the conversation?For the most part, but people like what they like and are free to do so, nothing wrong with that. This thread has basically dissolved itself. To say "X" interface is __ means nothing without context and shows a typical follower knee jerk reaction to what others say. This hobby has sooo much of this pile on mentality. Although, it isn't (and shouldn't be) a requirement to have an engineering degree to enjoy / understand every piece of gear. However, short of being a plug and play person (which is totally fine), if one chooses to get a bit more into the technical side of things, it behooves the individual to research AND experiment to get a better understanding of whats going on and to determine what best fits THEIR environment /setup Every product is different and usually has one or two interfaces that work best from the design intent (many have significant differences) - its not really that hard to understand or accept. |
Far from having ‘dissolved itself‘ I sincerely hope that this thread might lead serious designers to reconsider whether rather than using a low end, convenience consumer interface with all its known foibles to transmit high quality audio, one might usefully revisit more appropriate formats (optical, I2S, AES/EBU) to improve on what is at best an unacceptably wide range of outcomes with USB; I also note with a degree of puzzlement that members of the ‘bits are bits’ school of sitting on your ears are alive and well |
There are 2 reliable interfaces capable of transmitting DSD , ethernet and USB. If you're not interested then use optical, coax, or AES3. I2S was never intended for transfer between devices but on chip no more than an inch or two. There are a few DACs and streamers that have I2S just need to make sure what you're connecting to what is compatible. As far as jitter AES3 and coax will have more jitter than USB in well designed DACs. It's just the nature of the design, having the clock decided by the host like coax and AES3 causes more jitter than asynchronous transfer like USB. There's no puzzlement or spooky things at a distance bits are bits whether those bits are transferred by ethernet, USB, optical, coax or AES3 it's the same bits. |
My experience... Not to discount your experience or your ears, but I have tried all manner of these devices and find they make no difference .. in my system.... to me.. I have tried among others
As for jitter from servers and transports.. Asynchronous transfer is designed to eliminate that. The DAC asks for data packets at its pace and clocks them on down the line using its internal clocks. Any jitter from the source is therefore disregarded so if you hear a difference using devices as above, in theory it is not because they reduced jitter. That said, I don’t doubt you hear something. I’m just saying that attributing it to jitter flies in the face of everything we know about how this stuff all works. I’m also pretty sure we don’t really understand how all of this stuff works, nor do we really need to if we are getting the results we want. It would be interesting to use a source to feed an asynchronous DAC where you could vary the jitter and determine if you could hear it. |
one might usefully revisit more appropriate formats (optical, I2S, AES/EBU) to improve on what is at best an unacceptably wide range of outcomes with USB; I’m pretty sure that you will get an equally wide range of outcomes using these other formats. And reading your initial post, the problems you had with getting a reliable connection are not inherently USB problems since millions of others have absolutely no issues getting a reliable connection. The fact that you finally got it to work with a particular USB cable tells me something else was amiss. The best sounding connection we can debate, but not being able to get the source to communicate with the DAC via USB is highly unusual. I also have an Antelope DAC that I am extremely happy with although I do sometimes have to reboot my computer or the DAC to establish USB communication so maybe they do work better in a pro audio situation with that gear versus audiophile servers, and I sometimes have to toggle the internal word clock from lower rates to the maximum rate to get sound output, but a minor inconvenience for the wonderful sound at a reasonable cost. |
As for jitter from servers and transports.. Asynchronous transfer is designed to eliminate that. The DAC asks for data packets at its pace and clocks them on down the line using its internal clocks. Any jitter from the source is therefore disregarded so if you hear a difference using devices as above, in theory it is not because they reduced jitter. That said, I don’t doubt you hear something. I’m just saying that attributing it to jitter flies in the face of everything we know about how this stuff all works.+1. It's quite possible that a device that purports to be a USB reclocker (any device that receives and retransmits USB is a reclocker) is reducing noise on the USB signal to an audible degree. But the notion that this is because it has less jitter on the USB connection makes no sense. I believe that there are still a lot of DACs on the market that sound better using legacy interfaces (spdif, toslink, aes3) but I contend that this is either because the source of these signals (transport/streamer) has a better clock than the DAC, or the DAC has a particularly poor USB implementation. There is no technical reason why a DAC can't be implemented with a USB interface that outperforms legacy interfaces. SPDIF, Toslink, and AES3 all have an inherent flaw in that they are prone to jitter because the clock is embedded with the data. No matter how much you spend on cables, the connectors themselves introduce impedance discontinuities which create reflections which interfere with the waveform. I'm not saying that legacy interfaces can't delivery excellent results. But from an engineering perspective, the cost to do so exceeds (perhaps significantly) the cost to achieve similar performance from USB (or Ethernet). I think it's only a matter of time before the industry has dropped the legacy interfaces in favor of USB (or some future asynchronous digital transport interface). |
